On calm days, sunlight warms the ocean surface and drives turbulence

Science Daily  March 1, 2021
Over land, afternoon warming can lead to atmospheric convection and turbulence resulting in thunderstorms. Over the ocean, the afternoon convection also draws water vapor from the ocean surface to moisten the atmosphere and form clouds. The warming over the ocean is more subtle and gets stronger when the wind is weak. A team of researchers in the US (Oregon State University, NOAA Boulder Co) gathered lidar data around the clock for about two months. At one point, surface temperatures warmed each afternoon for four straight days with calm wind speeds, giving researchers the right conditions to observe a profile of the turbulence created in this type of sea surface warming event. The calm wind and warming air conditions occur in different parts of the ocean in response to weather conditions, including monsoons and Madden-Julian Oscillation events which are ocean-scale atmospheric disturbances that occur regularly in the tropics. To determine the role these changing temperatures play in weather conditions in the tropics, weather models need to include the effects of surface warming. This research gives us a more precise understanding of what happens when winds are low…read more. Open Access TECHNICAL ARTICLE